sn.35.111 Saṁyutta Nikāya (Linked Discourses)

“Bhikkhus, without directly knowing and fully understanding the eye, without developing dispassion towards it and abandoning it, one is incapable of destroying suffering. Without directly knowing and fully understanding the ear … the mind, without developing dispassion towards it and abandoning it, one is incapable of destroying suffering. But by directly knowing and fully understanding the eye … the mind, by developing dispassion towards it and abandoning it, one is capable of destroying suffering.”